Field of the Invention
The present invention relates to an ejection controller and an ejection control method for a molded article ejection device, such as an ejector, for an injection molding machine.
Description of the Related Art
Immediately after the start of a molding operation or in adjusting molding conditions in an injection molding machine, an operator may sometimes open a safety door, which covers the injection molding machine, and then remove molded articles and check them for condition. If a molded article removal machine is used during continuous molding such that the molded articles can be taken out on the opposite side of the injection molding machine to the side on which a control panel is located, moreover, setting for the check of the molded article condition may be changed so that the molded articles can be taken out on the control-panel side of the machine. Further, there is a method in which molded articles are checked for condition after being ejected by an ejector without being taken out by the molded article removal machine.
Japanese Patent Application Laid-Open No. 63-295227 discloses a technique in which a monitoring device in an injection molding machine is used to monitor an ejection operation and a mold opening operation of a movable mold half in a mold opening position. During a plurality of cycles of an injection molding process after initial setting, according to this technique, the injection molding process is repeated to collect determination reference values without regard to the result of the monitoring by the monitoring device, whereby the abnormality of the injection molding process is determined.
Japanese Patent Application Laid-Open No. 2009-61796 discloses a technique in which an image input unit is provided for acquiring images of the mold surfaces of movable and fixed mold halves of an injection molding machine. If a target image acquired by the image input unit is determined to be abnormal, according to this technique, an image of a mold apparatus is transmitted to an operator's terminal device so that the abnormality of molding can easily be ascertained.
In the technique in which the setting for the check of the molded article condition is changed so that the molded articles can be taken out on the control-panel side of the injection molding machine, there is the possibility of the operator standing near the control panel as he/she operates it, so that the molded article removal machine may approach and expose the operator to danger.
In the technique in which the molded articles are checked for condition after being ejected by the ejector, moreover, cavities from which the molded articles are ejected and dropped sometimes cannot be easily identified, especially if the molded articles are large in number.
In the techniques disclosed in Japanese Patent Applications Laid-Open Nos. 63-295227 and 2009-61796, the abnormality of the injection molding process is monitored based on image data captured by image pickup means such as a camera. However, these patent documents disclose neither countermeasures for the detection of abnormality nor a method for preventing abnormality.